Re: A couple of questions

"Paul Drake" <drak0nian_at_yahoo.com> wrote in message news:1ac7c7b3.0308300628.763fd9f_at_posting.google.com...

>
> the premise of throttling an OS process just so that it does not
> appear to be using 100% CPU seems backwards to me.

I don't think "appear" is the thing here. They may want to ensure that 20% of CPU is always available for other tasks for example. And no more than 20%.

> In w2k-land, we run nothing else except oracle instances on our oracle
> servers.

That seems to be the problem here. They appear to be running more than just oracle tasks. In that case and given that NT has no facilities whatsoever to apportion CPU resource other than basic time-sharing and I/O overlap within same priority group, there may be a need for a resource manager.

> the background processes aren't cranking along nicely. Put apps like
> OEM on management workstations, run sqlplus.exe on the server for
> administration.

That is very good advice in any case.

> Now, if oracle.exe (a single process, for this example) has no
> bottleneck with respect to I/O (say that a query is running nested
> loops with loss of IN subqueries)- why wouldn't the oracle.exe process
> use 100% CPU?

If you want another process (non-oracle) to also get some CPU. Some sites have been sold on a w2k box that can brew coffee as well as be a db server. We all know M$ does not recommend this for SQL Server. But watch what they expect of oracle servers...

> http://download-west.oracle.com/docs/cd/B10501_01/server.920/a96524/c10rsmgr.htm#24594
> "The effect of the Database Resource Manager is noticeable only in
> busy environments with high system utilization."

Says it all, ain't it?

>
> * If you want to control resource distribution within an
> instance, use the Database Resource Manager and turn off
> operating-system resource control.

that is awfully hard to do in w2k. The best way is probably by allocating one priority class for the oracle.exe and letting all other processes into a lower priority class. Then apportion the CPU use by oracle.exe. What is left will be spread by the OS on the lower priority class. This assumes a relatively static environment: doing this all the time would be murder! There is a lot to be said for the mainframe concept of partitions, it's ideal for this sort of situation.

> * If you have multiple instances on a node and you want to
> distribute resources among them, use operating-system resource
> control, not the Database Resource Manager."

That is the case indeed for multiple instances.

--
Cheers
Nuno Souto
wizofoz2k_at_yahoo.com.au.nospam